What does it mean that the Federal Reserve is "independent within the government"?

The Federal Reserve, like many other central banks, is an independent government agency but also one that is ultimately accountable to the public and the Congress. The Congress established maximum employment and stable prices as the key macroeconomic objectives for the Federal Reserve in its conduct of monetary policy. The Congress also structured the Federal Reserve to ensure that its monetary policy decisions focus on achieving these long-run goals and do not become subject to political pressures that could lead to undesirable outcomes. So, members of the Board of Governors are appointed for staggered 14-year terms and the Chairman of the Board is appointed for a four-year term. Elected officials and members of the Administration are not allowed to serve on the Board.

The Federal Reserve does not receive funding through the congressional budgetary process. The Fed's income comes primarily from the interest on government securities that it has acquired through open market operations. Other sources of income are the interest on foreign currency investments held by the Federal Reserve System; fees received for services provided to depository institutions, such as check clearing, funds transfers, and automated clearinghouse operations; and interest on loans to depository institutions. After paying its expenses, the Federal Reserve turns the rest of its earnings over to the U.S. Treasury.